Progress report and electrical question.

[jfugate]

Bob:

You're right, I forgot about the voltage conversion, which makes the 5.5 amps at only 77 watts as you show, and thus less than 0.8 amp at 120VAC. The layout circuit at 15 amps is loaded with capacity at that rate ...

[Anonymous]

The layout itself won't draw all that much current.

For arguement's sake, lets suppose that:

You're running 10 locomotives at a time, each pulling 20 lighted passenger cars.....

10 X 3/4 amp + 200 X 30 miliamps = 7.5 amps + 6 amps = 13.5 amps @ 14 VDC (DCC) Lets further suppose that you've run streets all over and have street lights running to give you another 5 amps of current at 12 VDC. So far you're up to 189 + 60 = 249 watts. Throw in a few inefficiencies and you're up to 300 watts. No big deal.

The support stuff in the room is what'll draw the current. Lighting? I've got 4 light fixtures, each with two 60 watt bulbs on a dimmer switch. That's 480 watts. If or when I want more lighting, THAT's where the load will be on my layout.

Heaters and AC units are even worse.

Mark in Utah

[cwclark]

I kind'a did what Joe did..i have the lighting on two different circuits (one for the flourecent lights, and nine color bulbs on another and the train on another one...they are 20 amp circuits but the train power has surge protection...don't need lightening to wipe out the whole thing...Chuck

[Anonymous]

QUOTE: Originally posted by jfugate

Yep, it depends on the size of the layout.

Trainnut gives the basic rule of thumb 100 watts = 1 amp.
....I expect at most there will be up to 4 trains in motion at a time on the layout, with a couple more yard switchers in operation. Each train could have 4-5 locos in it (head end + helpers). I model the 1980s so we're talking diesel locos here. Modern low-amp diesels normally take about .25 amps each, so 22 locos would total up to about 5.5 amps ... plenty of room to spare on the 15 amp circuit.

Remember Joe:
It's wattage that is usually the goverering factor: your 5.5 amps is at 14 volts which is 77 watts, while the 15 amp circit breaker is at 120 volts which is 1800 watts. The supply is a lot greater then the demand.

In my train room I have a light switch at the door that controls several recepticales and the layout is plugged into them, so when I leave the room and turn off the lights I can turn off the layout at the same time.

Have a good day
Bob

[MisterBeasley]

If you have the option for adding a separate circuit just for the air conditioner, that's a good idea. Any other big-draw items like electric heaters should have their own circuits, too. Consider isolating "surge" devices like big motors, refrigerators, etc.

Provide convenient outlets for soldering irons, drills and stuff. It's a lot easier and safer than dragging extension cords and terminal strips all across the room.

Plan ahead! Even if you don't have AC right now, it's a piece of cake to add the extra outlet and breaker while the walls are all torn apart, but much harder later when the drywall is up and your benchwork is in place.

[jfugate]

Yep, it depends on the size of the layout.

Trainnut gives the basic rule of thumb 100 watts = 1 amp.

My HO Siskiyou Line has about 1100 sq ft of benchwork area, and I have five 15 amp circuits dedicated to it. Four of those circuits are for lighting, the other one is for the layout.

I expect at most there will be up to 4 trains in motion at a time on the layout, with a couple more yard switchers in operation. Each train could have 4-5 locos in it (head end + helpers). I model the 1980s so we're talking diesel locos here. Modern low-amp diesels normally take about .25 amps each, so 22 locos would total up to about 5.5 amps ... plenty of room to spare on the 15 amp circuit.

[Anonymous]

Lights are the biggest load. 100 watts = 1 amp. I have found that even small layouts use a lot of wattage in the lighting department. The other issue with lighting is that it is often an after thought, Thus straining circuits that were already close to max. If is convienient now, put in another circuit. I doubt that you will regret it later and if the layout grows you will be set.

[Anonymous]

Another lamp wouldn't be an issue, and if the DCC stuff will only draw 100 watts that shouldn't be an issue. I probably won't be able to run the microwave, refrigerator, air conditioner, and all the power tools at the same time though[:)]
Right now I have two receptacles wall mounted underneath the benchwork and overhead track lighting. Is there anything else that would be of use electrically? Are four outlets enough for under the layout? Actually three because one will be used for a spike strip at the workbench.
Thanks.

[jrbernier]

It should be no big issue. A typical 5 amp booster sould not use more than 100 watts of power - Can you add another lamp to the room circuit?

Jim

[Anonymous]

I had a very productive weekend and was able to put together about half of the benchwork I had intended. I did, however get a surprise when my future brother-in-law showed up and went to work adding some lights, and outlets to the layout area. This isn't completely done and can still be modified.
I am wondering if there are electrical aspects I should be considering and am not; I would greatly appreciate comments and ideas.
Additionally, can someone tell me about how much wattage a layout demands? I suppose it will be a midsize DCC layout. Is a 12' x 5' "L" medium or small? I ask this because I have a lot of demands already on a 20 amp circuit and wonder if I will need another isolated circuit just for the layout.
Again thanks all of you for your tolerance and guidance.